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	Aabel 3 Overview Statistics & Multivariate Data Analysis Interactive Visualization & Scientific Graphing Thematic Maps & Map Projection Utilities Dynamic Data Exploration Worksheets, Data Import, and Management Tools Data Manipulator Data Filtering Tools Graphic Export Formats

Aabel Worksheets, Data Management
Features, and Utilities

Worksheets are Aabel's data storage mechanism, and provide numerous data management functions and utilities. They also act as dynamic data sources for data analysis and visualization.

Supported Data Import Formats

Aabel provides importers for:

Excel format: 95, 97-2004 workbook (.xls)
Delimited text data (tab, comma, semicolon, space, etc.)
Fortran formatted data
Delimited numeric matrix data
Binary numeric matrix formats (8 bit, 16 bit, 32 bit, and 64 bit data)
dBase (II, III, IV) formats
Arc/Info Ungenerate
Mapgen
Matlab
Splus
ArcView shape files

To view the UI for delimited and shape file importers, click here.

Supported Variable Types

Aabel support diverse variable types:

Numbers (any legal numerical representation with no explicit sample space)
Cartographic coordinates:
- Longitude, Latitude
- Easting, Northing
Directional/orientational data:

Trend
Dip/Plunge
Azimuth

Date and Time (30 built-in date & time formats, and tools for custom-defining a format)
Text (with Unicode support)

Numbers of Rows & Columns

Aabel does not impose limits on the number of rows and columns in worksheets. The limitation is mainly related to the speed penalty imposed by:

Currently available hardware technology and the CPU resources
Physical memory available to the application

Other factors that can impose speed penalty are (i) large amounts of complex Unicode textual data, and (ii) use of complex symbols, or Unicode symbols for graphing large data sets.

Worksheet Utilities

Quality Control of Numeric Data

Aabel's quality control tools allow:

Displaying report summary statistics for each variable with a single click
Checking the number of missing values of a variable (discontinuous data, etc.)
Detecting out-of-range values (impossible values, punching errors, etc.) and highlighting them in the corresponding worksheet rows
Dealing with out-of-range values using different options

Pre-defined Units of Weights and Measures

Data stored in different worksheets or databases do not always have the same units of measurement. This may result in inconsistencies during data analysis and processing from multiple data sources. Aabel provides the optional feature of tagging the variables with their appropriate units.
A wide range of pre-defined units of weights and measures are included. Once you set or change your preferred units in the global preferences, during data analysis, charting, or data processing, Aabel checks the tagged variables for unit inconsistencies and transforms the data to your preferred unit without modifying the source data.

Aabel Worksheet Map Projection Utilities

If the polygons are imported as numeric data with no explicit sample space, cartographic coordinate transformations are required to store the data as longitude-latitude or to define them using a different projection system. Aabel provides map projection utilities built into its worksheets to allow the following transformations:

Forward projections, which represent transformation of the spherical longitude-latitude coordinate system of the earth to the X-Y coordinate system of paper
Inverse projections, which allow you to transform the initially projected coordinates back to longitude and latitude

Aabel includes 19 projection systems, the geographic coordinate system, and the state plane coordinate system.

The supported systems include:

Geographic
Albers Conical Equal Area
Azimuthal Equidistant
Equidistant Conic
Gnomonic
Hammer
Interrupted Goode Homolosine
Lambert Conformal Conic
Mercator
Miller Cylindrical
Mollweide
Orthographic
Polar Stereographic
Polyconic
Robinson
State Plane Coordinate System (USA)^*
Stereographic
Transverse Mercator
Universal Transverse Mercator (UTM)
Van der Grinten

^* The state plane coordinate system is specific to US, and once a zone and the datum are selected, Aabel will automatically use the state-legislated projection and unit for that zone, as defined in NAD27 and NAD83.

You can execute coordinate transformation for any number of selected coordinate pairs rapidly, as shown in the image below:

The Worksheet Notebook

The worksheet notebook has four functions:

It displays a list of all variables present in the worksheet
If a worksheet has been generated from the results of data filtering, the user-defined filter criteria will be stored in the worksheet notebook
If the worksheet has been generated from cross-tabulating and pivoting, the information regarding the original worksheet file, primary and secondary split variables, etc., will be stored in the worksheet notebook
It provides a text area for storing notes, e.g., data source references, etc.

To view the UI, click here.

The Worksheet Data Management Tools

Cross-interpolation
Sorting with a single as well as with multiple keys
Transposing
Merging multiple textual data columns into one column
Merging numeric or textual data without concatenating
Reordering rows and columns
Providing a palette for rapid scanning through data columns in a worksheet with large number of variables or for bringing a specific data column into the field of view
Recoding text, or numeric values to categories
Pivoting and summarizing multidimensional data (cross tabulation)
Splitting and pivoting saw data
Splitting and recoding a categorical variable to binary dummy variables
Stacking columns
Grouping data objects based on values of a categorical variable: mapping categorical data to markers
Grouping data objects based on values of a numeric variable: mapping numeric values to marker color properties
Mapping object markers to categorical data
Mapping marker codes to marker
Multidimensional data filtering tools for generating subsets of data

The Worksheet Formula Editor

The formula editor integrated into Aabel worksheets, provides 46 pre-defined mathematical and statistical functions, and includes standard as well as Boolean/conditional operators.

In Aabel, variables are identified by names, and not by the position of worksheet columns. However, to facilitate sequential calculations, the formula editor provides functions that operate on variables by indices instead of names.
Aabel worksheet operations are column based. However, the optional feature of addressing worksheet row indices enables addressing the worksheet cells explicitly.
In addition to functions provided for column-wise calculations, the formula editor provides a number of functions for row-wise calculations.
Assign and calculate commands are provided for applying the same formula to multiple columns.

The Worksheet Markers (Colored Symbols Used for Data Representation)

Markers are colored graphical symbols that allow identifying the plotted data, i.e., data sources, individual or groups of data objects, data series, etc.

The Significance of Markers

Object markers:

Each worksheet has a global marker that is shared by all data objects (the collective data source marker). The significance of this marker is to differentiate data that are sourced from different worksheets.
Each worksheet row can have its own local marker, i.e., local markers identify individual or groups of data objects based on uniqueness of the local marker (defined by its symbol, color, and size). The significance of this marker is to differentiate groups of data objects (see the right-hand side image).
When you change markers that represent data sources or groups of data objects on a graph, the change will be dynamically updated in the worksheet, and vice versa.

Variable markers:

In a graph that displays data series, the variable markers are initially taken from a pre-set definition for identifying variables in the order they are stored in the source worksheet. You can define and hot-link marker and other properties (e.g., fill color, line thickness, type, and color) to variables (worksheet columns).

Aabel Marker Symbols

Aabel provides 175 marker symbols, each of which can be scaled from 50 to 200% of the initial size (100%) in 20 steps.
The Aabel marker palette also has a blank "symbol" to allow removing markers from a graph:
This can be useful, for example, to compare regression curves without displaying data points.

Unicode Characters/Symbols/Glyphs

The Unicode palette can hold 176 characters/symbols/glyphs, each of which can be scaled from 50 to 200% of the initial size (100%) in 20 steps.
This palette can be customized, i.e., each item of the palette can be replaced by another Unicode character/symbol/glyph from the System character palette.

Aabel Worksheets, Data ManagementFeatures, and Utilities